A transaction control layer for a signaling gateway that encapsulates multiple signaling systems into a single signaling interface for use by an advanced service node deployed in a telecommunications network. The transaction control layer performs call and resource state management functions for the...http://www.google.com.au/patents/US20010055375?utm_source=gb-gplus-sharePatent US20010055375 - CALL AND CIRCUIT STATE MACHINE FOR A TRANSACTION CONTROL LAYER OF A COMMUNICATIONS SIGNALING GATEWAY
